Correcting what you don’t see?

Mi

My son’s daycare told me he’s a pusher. He doesn’t share toys and when another child approaches, he will shove them off to take the toy. Worse yet, he will go take a toy from another kid and kind of push them to get it!

She said we have to work together to correct it, but he’s 2 years old and an only child, and NEVER does that at home. At home he’s gentle, sweet, and hands me things when I ask for them. So I’m not sure what to do in order to correct the behavior. He’s also been in daycare for 13 months already so it’s not like being around other kids is new.

What do I do to help him learn, if I never get the opportunity to correct the behavior?